Publications by authors named "Vivan L"

During an IRONMAN, the pacing strategy in the running segment differs significantly between sexes. However, it is unknown if sex affects the running pace in shorter triathlon events. This study compared the pacing strategy between sexes during a 5-km running test performed following a 20-km cycle (sprint triathlon distances).

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Background/objectives: Sarcopenia is a muscular disease characterized by loss of muscular strength and function, affecting mainly women, and associated with increased mortality risk. The aim of this study was to compare active women with inactive women of different age groups regarding muscle mass, strength, and muscle quality.

Methods: This study included 147 women (85 runners and 62 inactive), divided into <50 and ≥50 years old.

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Running performance is crucial for triathlon performance. However, the prior bout of cycling may affect the running split time. This study compared the triathletes' cycling plus running (C+R) time, when cycling was performed at three different intensities and running was maximal.

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Purpose: Physical inactivity is considered an important risk factor for osteoporosis, however, some athletes performing extremely high training volumes can also develop bone mass loss. Moreover, the effect of total body mass or body surface area on bone mineral density remains controversial. Therefore, the aim of this study was to compare the absolute bone mineral density and bone mineral density adjusted to body surface area between amateur triathletes and nonactive women.

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The present study aimed to compare V̇Omax (absolute, adjusted to total body mass, and adjusted to lean mass) in recreational runners and sedentary women < and > 50 yr and verify the effect of aging and physical activity level on the three types of V̇O max expression. The study included 147 women:85 runners (45.7 ± 14.

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Purpose: Endurance sports performance is influenced by several factors, including maximal oxygen uptake (⩒Omax), the percentage of ⩒Omax that can be sustained in endurance events, running economy, and body composition. Traditionally, ⩒Omax can be measured as an absolute value, adjusted for body mass, reflecting the athlete's central capacity (maximal cardiac output), or adjusted for lean mass (LM), reflecting the athlete's peripheral capacity (muscular oxidative capacity). The present study aims to evaluate absolute, total body mass, and lower limb LM-adjusted ⩒Omax, ventilatory thresholds (VT), respiratory compensation points (RCP), and body composition during two training periods separated by 8 months.

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Male athletes tend to outperform female athletes in several endurance sports. Maximum cardiac output can be estimated by maximal oxygen consumption (V˙O2max), and it has been established that men present V˙O2max values about 20% higher than women. Although sex differences in V˙O2max have already been well studied, few studies have assessed sex differences with regard to muscle oxidative capacity.

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Performance in endurance sports decreases with aging, which has been primarily attributed to cardiovascular and musculoskeletal aging; however, there is still no clear information on the factors that are most affected by aging. The aim of this study was to compare two groups of runners (< 50 and > 50 years of age) according to their absolute, weight-adjusted maximal oxygen uptake (V̇Omax), lower limb lean mass-adjusted V̇Omax, ventilatory threshold, and respiratory compensation point (RCP). A total of 78 male recreational long-distance runners were divided into Group 1 (38.

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The purpose of this study was to verify the physiological and anthropometric determinants of triathlon performance in female and male athletes. This study included 40 triathletes (20 male and 20 female). Dual-energy X-ray absorptiometry (DEXA) was used to assess body composition, and an incremental cardiopulmonary test was used to assess physiological variables.

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Maximal oxygen uptake (V˙O2max), ventilatory threshold (VT) and respiratory compensation point (RCP) can be used to monitor the training intensity and the race strategy, and the elucidation of the specificities existing between the sexes can be interesting for coaches and athletes. The aim of the study was to compare ventilatory threshold (VT), respiratory compensation point (RCP), and the percentage of the maximal aerobic speed (MAS) that can be maintained in a triathlon race between sexes. Forty-one triathletes (22 men and 19 women), 42.

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Lepidopteran pests are major factors limiting soybean productivity in South America. In some cases, effective management of these species requires the use of foliar insecticides. For sustainable use of these insecticides, they should only be applied when insect population size exceeds an economic threshold.

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Introduction: The maximum oxygen uptake (V˙Omax), the maximum rate of oxygen that can be sustained before the onset of blood lactate accumulation, and the metabolic cost of locomotion are the main physiological factors associated with long-distance running performance. The latter is known as the running economy. Generally, runners reach peak performance in long races between 25 and 30 years of age, with a progressive decline occurring thereafter.

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Objective: To compare the levels of depression, anxiety, physical activity, and mobility restrictions between the first wave in June 2020 and the fourth wave in January 2022 of the coronavirus disease-2019 (COVID-19) pandemic in Brazil.

Patients And Methods: Brazilian citizens answered a self-administered questionnaire that included questions related to personal information, mobility restriction levels, physical activity levels, and the status of mood disorders in June 2020 (n=1853) and January 2022 (n=728).

Results: The levels of mobility restrictions (p<0.

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Background: The coronavirus disease 2019 (COVID-19) pandemic and the necessary social isolation and distancing measures - that were adopted to prevent spreading the virus, including the suspension of university classes - negatively impacted the mental health of young adults. The aim of the current study was to investigate whether returning to online classes, even not presential, during the social isolation of the COVID-19 pandemic, affected the mental health of university students.

Methods: Forty students (10 men and 30 women) (age, 22.

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Soybean stem necrosis is caused by cowpea mild mottle virus (CPMMV), transmitted by the whitefly . CPMMV has already been recorded in all major soybean-producing areas of Brazil. The impacts caused by CPMMV to the current Brazilian soybean production are unknown, thus the main objective of this study was to evaluate the effects of CPMMV infection on the main important soybean cultivars grown in the Southern and Midwestern regions of Brazil.

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The burrower bug Scaptocoris castanea is an important soybean and pasture pest in Brazil, with an underground habit feeding directly on the sap of the roots. Underground habit hinders control and knowledge of the biology and physiology of this pest. This study describes the anatomy, histology, ultrastructure and symbionts of the midgut of S.

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The burrower bug Scaptocoris castanea Perty, 1830 (Hemiptera: Cydnidae) is an agricultural pest feeding on roots of several crops. The histology and ultrastructure of the salivary glands of S. castanea were described.

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Equimolar amounts of lactobionic acid and sorbitol may be obtained in a reaction catalyzed by the enzymes glucose-fructose oxidoreductase and glucono-δ-lactonase, which are found in the periplasm of Zymomonas mobilis. These reactions are generally conducted using immobilized bacterial cells, and the cell treatment and immobilization steps are costly and time-consuming. This study evaluated alternatives to simplify the preparation of calcium alginate-immobilized biocatalyst and its application in different operation modes and types of reactors.

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The widespread use of antibiotics and anti-inflammatory has been more and more prominent. In spite of the proven pharmacological potential, its collateral effects are still being described. The fish oil is made of acids fatty polyunsaturated, as the omega 3.

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This work studied 17 insecticides belonging to nucleopolyhedrovirus (NPV), Bacillus thuringiensis (Bt kurstaki and Bt aizawai), benzoylureas (insect growth regulators [IGRs]), carbamates, organophosphates, spinosyns, and diamides against larvae of Helicoverpa armigera (Hübner), invasive species in the South American continent. Larvae of different instars were fed for 7 d with untreated or insecticide-treated diets. Mortality was recorded daily for 7 d, and surviving larvae were individually weighed on the seventh day.

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Nymphs and adults of the burrower bug Scaptocoris carvalhoi Becker feed on vegetal sap of their host plants through the roots, and little is known on the morphology and biology of its immature stage. Therefore, we aimed to characterize the immatures of S. carvalhoi by describing the egg and the morphology of each instar.

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Since seed coating with neonicotinoid insecticides was introduced in the late 1990s, European beekeepers have reported severe colony losses in the period of corn sowing (spring). As a consequence, seed-coating neonicotinoid insecticides that are used worldwide on corn crops have been blamed for honeybee decline. In view of the currently increasing crop production, and also of corn as a renewable energy source, the correct use of these insecticides within sustainable agriculture is a cause of concern.

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Nezara viridula (L.) is a cosmopolitan and polymorphic pentatomid. Several genetically determined types have been described due to body color variation in adults.

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The fertility life table of Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae) preying either on Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) caterpillars or on alternative prey Tenebrio molitor L. (Coleoptera: Tenebrionidae) under greenhouse conditions (30 +/- 5 degrees C, 61 +/- 23% RH) were studied. The life table was also determined for the pest T.

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